1 files changed, 21 insertions, 23 deletions

diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index 5d96914..87e7ed1 100644
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -179,28 +179,19 @@ EmitDwarfLineTable(MCObjectStreamer *MCOS, const MCSection *Section,
   }
 
   // Emit a DW_LNE_end_sequence for the end of the section.
-  // Using the pointer Section create a temporary label at the end of the
-  // section and use that and the LastLabel to compute the address delta
-  // and use INT64_MAX as the line delta which is the signal that this is
-  // actually a DW_LNE_end_sequence.
+  // Use the section end label to compute the address delta and use INT64_MAX
+  // as the line delta which is the signal that this is actually a
+  // DW_LNE_end_sequence.
+  MCSymbol *SectionEnd = MCOS->endSection(Section);
 
-  // Switch to the section to be able to create a symbol at its end.
-  // TODO: keep track of the last subsection so that this symbol appears in the
-  // correct place.
-  MCOS->SwitchSection(Section);
+  // Switch back the dwarf line section, in case endSection had to switch the
+  // section.
+  MCContext &Ctx = MCOS->getContext();
+  MCOS->SwitchSection(Ctx.getObjectFileInfo()->getDwarfLineSection());
 
-  MCContext &context = MCOS->getContext();
-  // Create a symbol at the end of the section.
-  MCSymbol *SectionEnd = context.CreateTempSymbol();
-  // Set the value of the symbol, as we are at the end of the section.
-  MCOS->EmitLabel(SectionEnd);
-
-  // Switch back the dwarf line section.
-  MCOS->SwitchSection(context.getObjectFileInfo()->getDwarfLineSection());
-
-  const MCAsmInfo *asmInfo = MCOS->getContext().getAsmInfo();
+  const MCAsmInfo *AsmInfo = Ctx.getAsmInfo();
   MCOS->EmitDwarfAdvanceLineAddr(INT64_MAX, LastLabel, SectionEnd,
-                                 asmInfo->getPointerSize());
+                                 AsmInfo->getPointerSize());
 }
 
 //
@@ -243,7 +234,8 @@ std::pair<MCSymbol *, MCSymbol *> MCDwarfLineTableHeader::Emit(MCStreamer *MCOS)
       0, // length of DW_LNS_set_epilogue_begin
       1  // DW_LNS_set_isa
   };
-  assert(array_lengthof(StandardOpcodeLengths) == (DWARF2_LINE_OPCODE_BASE - 1));
+  assert(array_lengthof(StandardOpcodeLengths) ==
+         (DWARF2_LINE_OPCODE_BASE - 1));
   return Emit(MCOS, StandardOpcodeLengths);
 }
 
@@ -446,7 +438,7 @@ void MCDwarfLineAddr::Encode(MCContext &Context, int64_t LineDelta,
   if (LineDelta == INT64_MAX) {
     if (AddrDelta == MAX_SPECIAL_ADDR_DELTA)
       OS << char(dwarf::DW_LNS_const_add_pc);
-    else {
+    else if (AddrDelta) {
       OS << char(dwarf::DW_LNS_advance_pc);
       encodeULEB128(AddrDelta, OS);
     }
@@ -1007,11 +999,13 @@ static void EmitPersonality(MCStreamer &streamer, const MCSymbol &symbol,
 namespace {
   class FrameEmitterImpl {
     int CFAOffset;
+    int InitialCFAOffset;
     bool IsEH;
     const MCSymbol *SectionStart;
   public:
     FrameEmitterImpl(bool isEH)
-        : CFAOffset(0), IsEH(isEH), SectionStart(nullptr) {}
+        : CFAOffset(0), InitialCFAOffset(0), IsEH(isEH), SectionStart(nullptr) {
+    }
 
     void setSectionStart(const MCSymbol *Label) { SectionStart = Label; }
 
@@ -1292,7 +1286,7 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
     Augmentation += "R";
     if (IsSignalFrame)
       Augmentation += "S";
-    streamer.EmitBytes(Augmentation.str());
+    streamer.EmitBytes(Augmentation);
   }
   streamer.EmitIntValue(0, 1);
 
@@ -1353,6 +1347,8 @@ const MCSymbol &FrameEmitterImpl::EmitCIE(MCObjectStreamer &streamer,
     EmitCFIInstructions(streamer, Instructions, nullptr);
   }
 
+  InitialCFAOffset = CFAOffset;
+
   // Padding
   streamer.EmitValueToAlignment(IsEH ? 4 : MAI->getPointerSize());
 
@@ -1368,6 +1364,8 @@ MCSymbol *FrameEmitterImpl::EmitFDE(MCObjectStreamer &streamer,
   MCSymbol *fdeEnd = context.CreateTempSymbol();
   const MCObjectFileInfo *MOFI = context.getObjectFileInfo();
 
+  CFAOffset = InitialCFAOffset;
+
   // Length
   const MCExpr *Length = MakeStartMinusEndExpr(streamer, *fdeStart, *fdeEnd, 0);
   emitAbsValue(streamer, Length, 4);